Biomedical subjects

E Schönau

Publications and source records attributed to E Schönau.

At least 19 recordsLinked to original sources

PubMed2005

Clinical characteristics of type 2 diabetes mellitus in overweight European caucasian adolescents.

AIM: To present the clinical features of Type 2 diabetes mellitus (T2DM) in overweight European Caucasian children and adolescents. METHODS: We report the clinical characteristics of 16 non-syndromal overweight European Caucasian adolescents with T2DM (10 boys, 6 girls, SDS-BMI in median +2.8, range +1.6 to +3.4) treated in 5 specialised centres for obesity and diabetes. RESULTS: None of the adolescents manifested with ketoacidosis. 13 were asymptomatic (3 adolescents with polyuria), 12 showed features of metabolic syndrome (dyslipidaemia or hypertension), 8 demonstrated acanthosis nigricans and 12 had relatives with T2DM. 11 adolescents were extremely obese and all patients were pubertal. Mean age at diagnosis was 14.2 years (range 11.0 - 16.9). Median insulin was 19 microU/ml, insulin resistance index (HOMA) 8.5, C-peptide 2.3 ng/ml, HbA1c 6.9 %, fasting blood glucose 176 mg/dl and blood glucose at 2 hours with the oGTT 229 mg/dl at manifestation. Fasting blood glucose and HBA1c were in the normal range in 4 and 6 adolescents respectively, while oGTT always fitted the diagnosis of T2DM. CONCLUSION: Since T2DM occurred in Caucasian overweight adolescents and is frequently asymptomatic, it is essential that clinicians perform diagnostic procedures to identify T2DM in high-risk groups of overweight Caucasian adolescents (extreme obesity, features of metabolic syndrome, relatives with T2DM).

Acanthosis Nigricans↗

PubMed2002

Biochemical markers of growth hormone (GH) sensitivity in children with idiopathic short stature: individual capacity of IGF-I generation after high-dose GH treatment determines the growth response to GH.

OBJECTIVE AND PATIENTS: To assess multiple dose-response relationships between three GH doses (1.5, 3.0 and 6.0 IU/m2) and nine different biochemical markers of GH sensitivity in a well-defined group of 17 children with idiopathic short stature (ISS). DESIGN AND MEASUREMENTS: Serum levels of IGF-I, IGF-II and IGFBP-3, and peripheral markers leptin, C-terminal propeptide of type I collagen (PICP) and N-terminal propeptide of type III collagen (PIIINP), alkaline phosphatase (AP) and osteocalcin (OC) were measured at the start and after 2 and 12 weeks of periods of no treatment, GH 1.5 IU/m2 and GH 3.0 IU/m2. Twelve-week washout periods were applied between the 12-week GH-treatment periods. High-dose GH treatment was given during the second year of study and all serum markers were measured at start, after 2 and 12 weeks and 1 year of GH 6.0 IU/m2. In 18 non-GH-treated children with ISS the same parameters were measured yearly. The bone resorption marker urinary deoxypyridinoline (DPD) was measured during 12-h day and night periods at start and after 2 weeks GH 1.5, 3.0 and 6.0 IU/m2. RESULTS: All markers were GH dependent, but the timing of maximal response varied among different markers. Height SDS at start, age at start and IGF-II at baseline were inversely related to the first-year growth response (r = -0.73, P = 0.001; r = -0.53, P = 0.03; and r = -0.53, P = 0.03, respectively). Some statistically significant correlations between biochemical responses on low GH doses (1.5 or 3.0 IU/m2) and second-year growth response were found, but these showed no consistent pattern. However, all changes in IGF-I SDS after GH 6.0 IU/m2 measured either after 2 or 12 weeks or 1 year correlated significantly with the second-year growth response (r = 0.55, P = 0.02; r = 0.81, P = 0.001; and r = 0.86, P < 0.001, respectively). Baseline or GH-stimulated levels of peripheral markers did not correlate with the growth response. CONCLUSION: The individual capacity of IGF-I generation after high-dose GH treatment (6.0 IU/m2) determines the growth response on high-dose GH treatment. Peripheral markers do not seem to play a role in growth prediction of children with ISS.

Biomarkers↗

PubMed2002

The bone behind a low areal bone mineral density: peripheral quantitative computed tomographic analysis in a woman with osteogenesis imperfecta.

Areal bone mineral density (BMD) is the most widely used densitometric parameter. However, this approach makes it difficult to understand the structural basis of bone diseases, because a large number of bone properties are integrated into a single number. This is exemplified in the present case of a 27-year-old woman with osteogenesis imperfecta type I. Peripheral quantitative computed tomographic analysis at the radial metaphysis and at the radial diaphysis revealed a decreased areal BMD at both sites (z score -3.9 and -3.4, respectively). Yet, the structural basis for this decrease was different for the two locations: At the distal radius areal BMD was decreased because volumetric BMD was very low, whereas bone size was above the mean of the reference range. At the proximal radius areal BMD was decreased, because bone size was very low but volumetric BMD was above average. Bone mineral content of the radial diaphysis was very low for forearm muscle size, a finding which is compatible with Frost's hypothesis that the mechanostat setpoint is increased in osteogenesis imperfecta.

Journal Article↗

PubMed2001

On longitudinal bone growth, short stature, and related matters: insights about cartilage physiology from the Utah paradigm.

Precursor cell division in growing cartilage determines human height, the lengths of the spine and limb bones, the alignment of joints, spines and limbs, and the ratio of spinal length to limb length. That division also helps to determine the sizes and shapes of joints, apophyses and epiphyses. Ideas about what controls those facts are changing. To former views, in which mainly genetic and humoral factors controlled them, the Utah paradigm of skeletal physiology adds long-overlooked biomechanical including muscular factors. These three kinds of factors would collaborate in controlling the precursor cell division that determines the above skeletal features. Problems with that control clearly cause or help to cause many clinical disorders. Examples include short stature, gigantism, premature and delayed skeletal maturation, some changes in fracture patterns associated with puberty, joint malalignments, congenital hip dysplasia, scoliosis, limb torsions, the ball-and-socket ankle, and some skeletal abnormalities in Marfan's syndrome and the osteochondrodystrophies. The physiology such things depend on has matured sufficiently to justify a review for pediatricians, endocrinologists and other clinical specialists, and many basic scientists.

Animals↗

PubMed2001

A new and accurate prediction model for growth response to growth hormone treatment in children with growth hormone deficiency.

OBJECTIVE: To identify parameters which predict individual growth response to recombinant human GH (rhGH) therapy and to combine these parameters in a prediction model. DESIGN: Fifty-eight prepubertal patients with GH deficiency (17 females) participated in this prospective multicenter trial with 1 year of follow-up. METHODS: Auxological measurements, parameters of GH status and markers of bone metabolism were measured at baseline and at 1, 3 and 6 months after the start of rhGH treatment. Correlations with height velocity during the first 12 months of treatment (HV+12) were calculated. Prediction models were derived by multiple regression analysis. RESULTS: The model which best predicted HV+12 combined the following parameters: pretreatment bone age retardation as a fraction of chronological age, pretreatment serum levels of IGF-I, urinary levels of deoxypyridinoline (a marker of bone resorption) after 1 month of treatment and height velocity after 3 months of treatment. This model explained 89% of the variation in HV+12 with a standard deviation of the residuals of 0.93 cm/year. Defining successful rhGH therapy as a doubling of pretreatment height velocity, the model had a specificity of 90% and a sensitivity of 100% in predicting therapeutic success. CONCLUSIONS: This model is an accurate and practicable tool to predict growth response in GH-deficient children. It may help to optimize rhGH therapy by individual dose adjustment and contribute to improved overall outcomes.

Adolescent↗

PubMed2000

Asp361Val Mutant of alkaline phosphatase found in patients with dominantly inherited hypophosphatasia inhibits the activity of the wild-type enzyme.

Hypophosphatasia is characterized by the hypomineralization of bone associated with the mutation of the tissue-nonspecific alkaline phosphatase (TNSALP) gene. Although the disease is usually autosomal recessive, an autosomal dominant form is also recognized. Approximately 50 mutations have been found in the TNSALP gene in patients with hypophosphatasia. However, the mutations identified to date do not seem to account for the dominantly inherited form of the disease. We have examined a German family in which the father and all 4 children were affected with hypophosphatasia, whereas the mother was healthy. The affected members of this family showed premature loss of deciduous teeth at or shortly before 2 yr of age and low levels of serum ALP with elevated levels of urinary phosphoethanolamine. DNA analysis by direct sequencing revealed a heterozygous missense mutation that caused the conversion of amino acid Asp to Val at position 361 (D361V) in the patients. Another substitution was detected in exon 12 (Val to Ala conversion at codon 505: V505A) in 1 allele of the mother and 3 children, indicating no association of the substitution with the disease. Reconstruction experiments demonstrated that the D361V mutant protein lost its enzymatic activity and that it inhibited the function of wild-type enzyme when coexpressed in COS-7 cells. On the other hand, the V505A mutant exhibited enzymatic activities equal to those of the wild-type ALP. It is likely that the mutant D361V protein forms dimers with the wild-type protein, and the protein-protein interaction contributes to the dominant effect of the mutant D361V. The mutation that causes D361V is the first one proven to be associated with the dominant form of hypophosphatasia.

Adult↗

PubMed2000

The "muscle-bone unit" in children and adolescents: a 2000 overview.

In former views hormones, calcium, vitamin D and other humoral and nonmechanical agents dominated control of postnatal bone strength (and "mass") in children and adolescents. However later evidence that led to the Utah paradigm of skeletal physiology revealed that this control depends strongly on the largest mechanical loads on bones. Trauma excepted, muscles cause the largest loads and the largest bone strains, and these strains help to control the biological mechanisms that determine whole-bone strength. That makes the strength of children's load-bearing bones depend strongly on growing muscle strength and how bones respond to it. Most hormones and other nonmechanical agents that affect bone strength can help or hinder that "bone strength-muscle strength" relationship but cannot replace it. In addition some agents long thought to exert bone effects by acting directly on bone cells, affect muscle strength too. In that way they could affect bone strength indirectly. Such agents include growth hormone, adrenalcorticosteroid analogs, androgens, calcium, genes, vitamin D and its metabolites, etc. Thus bone and muscle do form a kind of operational unit. It is part of the Utah paradigm that supplements earlier views with later evidence and concepts. The paradigm explains how the "bone strength-muscle strength" relationship works. This article provides an overview of that physiology, and some of its implications for pediatric endocrinologists.

Adolescent↗

PubMed2000

Chemiluminescence immunometric assay for measuring osteocalcin in healthy children.

Osteocalcin (OC) was measured in serum samples from 92 children and adolescents (57 females, 35 males) by a two-site chemiluminescence immunometric assay (Nichols Institute Diagnostics, USA), which recognizes the 1-19 region of the whole molecule as well as the large N-terminal midregion fragment representing the main part of OC in serum. The highest OC levels are measured between the age of 10-15 years. The linear correlations between OC and alkaline phosphatase were 0.65 (p < .01) for total alkaline phosphatase (TAP) and 0.61 (p < 0.1) for bone alkaline phosphatase (BAP).

Adolescent↗

PubMed1999

Age at menarche and cortical bone geometry in premenopausal women.

Previous studies have suggested that the timing of puberty might have an impact on the adult skeleton. What composite of bone structure could be affected by the timing of puberty is unknown at present. In this study, we evaluated the relationship between age at menarche and bone cortex geometry at the distal radius. Using peripheral quantitative computed tomography, we determined total area of the radial cross section, cortical bone area, periosteal cortical perimeter, endosteal cortical perimeter, and cortical width in 169 healthy premenopausal women aged 40-45 years. When stratified according to age at menarche (early, <12 years In = 22]; intermediate, 12-14 years [n = 118]; late, >14 years [n = 29]), only endosteal cortical perimeter varied significantly between the groups (p = 0.02, by analysis of variance), the mean value being 10% higher in the late compared to the early menarche group. However, weight and body mass index also exhibited significant variations between groups. After adjustment for weight the differences in endosteal cortical perimeter remained significant (p = 0.03). In multiple regression analysis, endosteal cortical perimeter was the only parameter of cortex geometry, which was independently associated with age at menarche. In a model including height and weight, age at menarche explained about 2% of the variability in endosteal cortical perimeter (p = 0.04). These data suggest that the bone marrow cavity of the distal radius may be slightly larger when puberty occurs later. Whether this marginal effect influences fracture risk in later life appears questionable.

Adolescent↗

PubMed1998

Does leptin have an effect on bone in adult women?

Recent studies have implicated leptin in the modulation of bone mass during skeletal development. Whether leptin also exerts an influence on bone after growth has stopped is unknown at present. In this cross-sectional study on 94 women (60 premenopausal, 34 postmenopausal) aged 40-60 years, we analyzed the relationship between serum leptin and bone density and bone cortex geometry and bone metabolism. Total and trabecular bone density as well as total and cortical bone area were determined by quantitative computed tomography (QCT) at the distal radius. Bone metabolism was assessed by measuring bone-specific alkaline phosphatase, osteocalcin, procollagen type I C-terminal propeptide (PICP) and collagen type I C-terminal telopeptide in serum, and deoxypyridinoline in urine samples. None of the indices of bone density or geometry was significantly related to leptin serum concentrations (P > 0.05) before or after adjustment for body mass index (BMI). PICP was associated with serum leptin in the postmenopausal group only (r = -0.40 after adjustment for BMI; P = 0.009). Yet, as none of the other markers of bone metabolism exhibited a significant correlation with serum leptin in any of the menopausal groups, this association is likely to be due to the influence of extraskeletal factors on PICP serum levels. Thus, it appears that leptin has less influence on the mature than on the growing skeleton.

Adult↗

PubMed1998

Problems of bone analysis in childhood and adolescence.

The monitoring of bone metabolism and skeletal development during childhood and adolescence is becoming increasingly important in the prevention of osteoporosis. This is especially important in patients with chronic disorders. The predominant changes in the skeletal system during growth occur as geometric adaptation processes which lead to an increase in bone mass and bone strength. These changes can be measured with linear absorption methods (single-photon absorptiometry, dual-photon absorptiometry, dual-energy X-ray absorptiometry), computed tomographic procedures (peripheral quantitative computed tomography, quantitative computed tomography), and sonographic procedures. The aim of this review is to explain the problems of interpretation of the investigations due to growth-dependent changes. Almost all methods and their parameters, such as bone density, spongiosa density, cortical density, ultrasound transmission velocity, etc., are influenced, in varying degree, by growth-dependent skeletal changes.

Adolescent↗

PubMed1998

Insulin-like growth factor binding protein-3 levels during early and late follow-up after surgery in acromegalic patients.

Disease activity in acromegaly is accurately reflected by growth hormone (GH) concentration during oral glucose tolerance test (OGTT) and insulin-like growth factor-I (IGF-I) levels, representing an integrated index of GH activity. This prospective study was performed to evaluate whether plasma IGF binding protein 3 (IGFBP-3) might also reflect the hormonal disease activity in pituitary acromegaly after operative treatment during early and late follow-up. Twenty-two acromegalic patients were studied. Data were obtained pre-, intra- and post-operatively in 13 cases. In 9 patients the acromegalic activity was studied only after treatment. The hormonal assessment included repeated blood samples for estimation of IGF-I, IGFBP-3 and repeated OGTTs. In each case 100 sigma g octreotide (Sandostatin lambda, Sandoz, Basel) was injected to test the acute response of GH, IGF-I and IGFBP-3. Intraoperatively, GH levels were estimated to examine acutely the influence of tumour reduction on GH levels. Patients were considered cured when GH levels (GH60min) were less than 2 ng/ml during OGTT 4 weeks after surgery. The data outlined that in patients with normalized GH60min levels, normalized IGFBP-3 levels were noticed 4 weeks and 12 months post-operatively. In non-cured patients normalized IGFBP-3 concentrations were found in 11 out of 15 cases in the late post-treatment phase. In contrast only 1 of 7 cured patients had persistently elevated IGF-I levels within the first month post-operatively, whereas no case of the non-cured patients had IGF-I values in the normal range. Despite these observations a strong correlation of IGF-I and IGFBP-3 did not exist before one year post-operatively -- either in the cured or in the non-cured patients. Serum IGFBP-3 in patients with pituitary acromegaly does not provide a predictive value of appreciable magnitude concerning cure or non-cure from the disease- whether examined early or late in the post-operative period. Absolute levels of IGFBP-3 may thus cause misinterpretation concerning cure of acromegalics after surgery.

Acromegaly↗

PubMed1998

Decreased trabecular bone mineral density in patients with phenylketonuria measured by peripheral quantitative computed tomography.

The bone mineral density (BMD) of 14 children, adolescents, and adults with phenylketonuria (PKU) on dietary treatment (age 5-28 y; 6F, 8M) was investigated using peripheral quantitative computed tomography (pQCT) of the distal radius. BMD of total (TBMD) and spongy bone (SBMD) were compared to those of healthy gender-, age-, weight- and height-matched controls. We found a significant decrease of SBMD in patients with PKU while TBMD was only slightly decreased, reaching no statistical significance. These results indicate minor changes of BMD in patients with PKU under treatment, which are more accentuated in the trabecular bone compartment. One additional patient who was untreated until the pQCT investigation at the age of 10 y also showed markedly decreased SBMD and TBMD.

Adolescent↗

PubMed1998

The effect of a specific strength-development exercise on bone mineral density in perimenopausal and postmenopausal women.

The objective of this study was to assess the effect of physical activity on bone density at the distal radius in healthy perimenopausal (23) and postmenopausal (60) women. The 83 women, aged 40-62 years, were randomized into two groups. The women participated in an exercise program of 40 minutes of jogging and 20 minutes of gymnastics three times a week for 1 year (group 1, n = 46) or 6 months (group 2, n = 37), respectively. Subjects in group 2 served as controls during the first 6 months. They were introduced to exercise classes after the first 6 months of the study and wore wrist weights (0.8 kg on each arm) during the gymnastics session. None of the women were on hormone replacement therapy (HRT). Results show a decrease in bone mineral density (BMD) during the first 6 months of the study in group 1 (2%, p < 0.01) and group 2, although this was not significant for the latter group (1.2%, n.s., p = 0.045). There was no significant change in osteocalcin serum concentration, fasting urinary calcium excretion, and calcium serum concentration during the first half of the study. After an additional 6 months, it was possible to stop BMD loss in both groups. Osteocalcin serum concentration significantly increased, and calcium serum concentration significantly decreased in groups 1 and 2. Fasting urinary calcium excretion decreased in both groups, although this was significant only in group 2 during the 1-year study. In conclusion, it proved possible to prevent BMD loss at the distal radius by our exercise program in perimenopausal and postmenopausal women. The effects of exercise may be general as well as localized. According to our results, additional localized benefits from a specific strength-development exercise may be seen.

Adult↗

PubMed1998

The development of the skeletal system in children and the influence of muscular strength.

In a study on 14 healthy children aged from 6 to 13 years, the volumetric spongiosa bone density (SBD), cortical bone density (CBD), bone cross-sectional area (BCSA), cortical area (CA), and bone strength index (BSI) at the distal radius were analyzed using peripheral quantitative computer tomography (pQCT Bone Scanner XCT-900, Stratec, Pforzheim, Germany). BSI values were calculated on the basis of the moment of resistance and cortical density using system integrated software. These parameters were correlated with grip strength measurements obtained using a grip dynamometer. There were age-dependent increases in BCSA (r = 0.68), CA (r = 0.78), BSI (r = 0.79). SBD and CBD, however, did not show an increase with age. Grip strength correlates strongly with the parameters of bone geometry BCSA (r = 0.8), CA (r = 0.86), and BSI (r = 0.9) at p < 0.01. SBD and CBD showed no significant correlation to grip strength. The results of this study suggest that an increase in cortical thickness and cross-sectional area represent the most important adaptation mechanisms of the growing bones in response to biomechanical usage. These parameters represent the most important factors of bone strength. Volumetric bone density (material characteristic) of spongiosa and cortical bone is an age-independent parameter which does not change significantly with increasing muscular strength in healthy subjects. These relationships must be considered when selecting parameters to be used as success criteria in studies on the influence of physical exercise on bone status.

Adolescent↗

PubMed1998

Serum leptin is suppressed by growth hormone therapy in growth hormone-deficient children.

Leptin is a hormone which is exclusively synthesized and secreted by adipocytes. As of yet, little is known about the complex interplay of hormones in the modulation of circulating leptin levels. To investigate the effect of growth hormone (GH) therapy on leptin, leptin serum concentrations were measured by a specific radioimmunoassay in 29 children with GH deficiency (21 boys, 8 girls; age range 3-14 years) before and after 1, 3 and 6 months of treatment with recombinant human GH. At baseline, serum leptin levels were identical to those of healthy children. Serum leptin correlated with body mass index (BMI; r=0.60, p < 0.001) and weight (r=0.48, p=0.004), but not with height, age, insulinlike growth factor 1, or insulinlike growth factor-binding protein 3, and there was no sex difference (p > 0.05). After 1 month of treatment, the leptin levels had decreased to 73+/-(SEM) 13% of individual pretreatment levels (p=0.002) and remained constant thereafter. While the correlation between leptin, BMI, and weight persisted throughout the study period, the changes in leptin concentrations during treatment were not associated with changes in BMI, weight, height, insulinlike growth factor 1, and insulinlike growth factor binding protein 3. In conclusion, this preliminary study demonstrates that serum leptin decreases during GH treatment in children with GH deficiency.

Adolescent↗

PubMed1997

Elevated levels of insulin-like growth factor (IGF) binding protein-3 in rheumatoid arthritis synovial fluid inhibit stimulation by IGF-I of articular chondrocyte proteoglycan synthesis.

The objective of this study was to quantify insulin-like growth factor (IGF) binding proteins (IGFBPs) in the synovial fluid (SF) and plasma of patients with rheumatic diseases and to study the role of these proteins in the regulation of cartilage proteoglycan (PG) synthesis. Immunological determination of IGFBP-2, IGFBP-3, IGF-I, IGF-II, interleukin-1 beta (IL-1 beta) and tumour necrosis factor alpha (TNF alpha) was undertaken in the SF and plasma of 115 patients with rheumatoid arthritis (RA; n = 53), osteoarthritis (OA; n = 44) and other rheumatic disorders. We also determined the effects of SF on bovine cartilage PG synthesis in culture. IGFBP-2 and IGFBP-3 were elevated in the plasma (by 38% and 28%, respectively) and SF (by 56% and 59%, respectively) of patients with RA compared to age- and sex-matched OA controls (determined by RIA and confirmed by Western ligand blot). IGF-I and IGF-II did not differ significantly between the two groups. OA SF, and, to a lesser extent, RA SF stimulated cartilage PG synthesis in culture, and more than 60% of this activity was neutralised by a specific monoclonal anti-IGF-I antibody. Human IGFBP-3 dose-dependently inhibited the stimulation of cartilage PG synthesis effected by SF or human IGF-I. In RA patients, the SF concentration of IGFBP-3 was positively correlated with SF levels of IL-1 beta and TNF alpha, with the serum levels of C-reactive protein and with the erythrocyte sedimentation rate. We concluded that IGF-I is, under the conditions studied, the most important anabolic factor in human SF with respect to articular cartilage PG synthesis. The bioactivity of IGF-I in joints is modulated by IGFBP-3, which is elevated in RA SF compared to OA SF. Elevated IGFBP-3 in RA SF may reduce the availability of IGF-I to articular chondrocytes, thus interfering with cartilage PG synthesis in RA.

Adolescent↗

PubMed1997

Vitamin D receptor genotypes and changes of bone density in physically active German women with high calcium intake.

Polymorphisms at the vitamin D receptor (VDR) gene have been reported to mediate important differences in bone mineral density (BMD) and bone metabolism. In this longitudinal study we examined the relationships between VDR genotypes and bone metabolism, changes in BMD and changes in ultrasound transmission velocity in a population of healthy unrelated German women. The study population comprised 50 physically active women (aged 43.3 to 62.8 years, 14 premenopausal, 36 postmenopausal) with a daily calcium intake of (mean +/- SD) 1045 +/- 338 mg, who had earlier participated in a longitudinal study on the association of physical activity and bone density and bone turnover. Each participant was genotyped for the BsmI polymorphism at the VDR gene locus. Markers of bone turnover (alkaline phosphatase, osteocalcin, procollagen type I C-terminal propeptide, collagen type I C-terminal telopeptide, tartrate-resistant acid phosphatase) were measured at baseline. BMD (determined by peripheral quantitative computed tomography at the distal radius) and ultrasound transmission velocity through bone (at calcaneus, patella and thumb) were analysed at baseline and 15 months later. The genotypic groups did not differ significantly (p > 0.05) in any of the parameters determined at baseline. Neither were there any differences between these groups in the changes of BMD or ultrasound transmission velocity during the study period. Thus, we conclude that in physically active German women with a relatively high calcium intake the impact of VDR genotypic polymorphisms on bone density, bone metabolism and changes in bone density may be of limited importance.

Alleles↗